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291.
292.
Ouni Youssef Flamini Guido Guerfel Mokhar Ben Youssef Nabil Douja Daoud Zarrouk Mokhtar 《International Journal of Food Science & Technology》2011,46(4):678-686
Chemlali olive oil has been blended with oils obtained from Oueslati and Chetoui varieties to improve the quality of the former one. Parameters such as acidity, acids compositions, phenol content, oxidative stability and volatile compounds were characterised for various blends Chemlali × Oueslati and Chemlali × Chetoui. The accumulation of volatiles originating from the lipoxygenase pathway in the monovarietal oils was different and closely dependent on the genetic store of each variety. The concentrations appeared to proportionally vary according to the relative proportion of each monovarietal oil in the mixtures. The blending process improved fatty acids by increasing the oleic acid content and decreasing the palmitic and linoleic acids levels of Chemlali oil. At 40% blending, oleic acid increased from 54% to 62%, while palmitic acid decreased from 18.59% to 16% when Oueslati and Chetoui olive oil was used. 相似文献
293.
Manal Farea Ahmad Sukari Halim Nurul Asma Abdullah Chin Keong Lim Khairani Idah Mokhtar Zurairah Berahim Kasmawati Mokhtar Abdul Qawee Rani Adam Husein 《International journal of molecular sciences》2013,14(6):11157-11170
Hertwig’s epithelial root sheath (HERS) cells play a pivotal role during root formation of the tooth and are able to form cementum-like tissue. The aim of the present study was to establish a HERS cell line for molecular and biochemical studies using a selective digestion method. Selective digestion was performed by the application of trypsin-EDTA for 2 min, which led to the detachment of fibroblast-like-cells, with the rounded cells attached to the culture plate. The HERS cells displayed a typical cuboidal/squamous-shaped appearance. Characterization of the HERS cells using immunofluorescence staining and flow cytometry analysis showed that these cells expressed pan-cytokeratin, E-cadherin, and p63 as epithelial markers. Moreover, RT-PCR confirmed that these cells expressed epithelial-related genes, such as cytokeratin 14, E-cadherin, and ΔNp63. Additionally, HERS cells showed low expression of CD44 and CD105 with absence of CD34 and amelogenin expressions. In conclusion, HERS cells have been successfully isolated using a selective digestion method, thus enabling future studies on the roles of these cells in the formation of cementum-like tissue in vitro. 相似文献
294.
This paper studies the necessary and sufficient conditions for near-optimal singular stochastic controls for the systems driven by non-linear stochastic differential equations with jump processes. The proof of our result is based on Ekeland’s variational principle and some delicate estimates of the state and adjoint processes. We apply convex perturbation for continuous and singular components of the control. It is shown that optimal singular controls may fail to exist even in simple cases. This justifies the use of near-optimal stochastic singular controls, which exist under minimal hypothesis and are sufficient in most practical cases. Moreover, since there are many near-optimal singular controls, it is possible to choose suitable ones that are convenient for implementation. The set of controls under consideration is necessarily convex. We prove that under an additional hypothesis, the near-maximum condition on the Hamiltonian function is a sufficient condition for near optimality. 相似文献
295.
Ouni Youssef Nabil Ben Youssef Zarrouk Mokhtar Flamini Guido 《International Journal of Food Science & Technology》2011,46(6):1245-1252
Olives (Olea europaea cv. Chemlali and Chetoui) used for oil production were stored, in plastic containers, at 5 °C for four different periods (0–3 weeks) before oil extraction. After storage, the oils were extracted from the fruits, and the acidity, peroxide value, coefficients of specific extinction at 232 and 270 nm, stability, pigments, total phenols, fatty acids, and volatile compounds were determined. The results showed that storage of fruits produced losses in the olive oil quality. During storage, a marked decrease in total phenols content was observed. The cultivar richer in phenols (862.16 mg kg?1 in Chétoui) had a lower loss (25%). On the contrary, in Chemlali olive oil, the starting value of 728.52 mg kg?1 decreased to 469.25 mg kg?1, with a loss of 35%. Chétoui and Chemlali olive oils presented the highest oxidative stability before storage (58.76 and 47.05 h, respectively), while the lowest values were recorded using olives stored for 3 weeks (54.46 and 43.43 h, respectively). The changes in the volatile bouquet were determined using headspace solid phase microextraction (HS‐SPME). Thirty compounds were characterised by GC–FID and GC–MS. Compounds belonging mainly to alcohols, esters, aldehydes, ketones and hydrocarbons chemical classes characterised the volatile profiles. 相似文献
296.
Amani Taamalli David Arráez Román Mokhtar ZarroukAntonio Segura-Carretero Alberto Fernández-Gutiérrez 《Food chemistry》2012,132(1):561-566
The present work describes a classification method of Tunisian ‘Chemlali’ olive oils based on their phenolic composition and geographical area. For this purpose, the data obtained by HPLC-ESI-TOF-MS from 13 samples of extra virgin olive oils, obtained from different production area throughout the country, were used for this study focusing in 23 phenolics compounds detected. The quantitative results showed a significant variability among the analysed oil samples. Factor analysis method using principal component was applied to the data in order to reduce the number of factors which explain the variability of the selected compounds. The data matrix constructed was subjected to a canonical discriminant analysis (CDA) in order to classify the oil samples. These results showed that 100% of cross-validated original group cases were correctly classified, which proves the usefulness of the selected variables. 相似文献
297.
Mazlin Bin Mokhtar Ahmad Zaharin Aris Mohd Harun Abdullah Mohd Kamil Yusoff Md. Pauzi Abdullah Abd. Rahim Idris & Raja Ibrahim Raja Uzir 《Water and Environment Journal》2009,23(3):219-228
The chemical characteristics of the surface water of Eucalyptus River, in Maliau Basin, were studied based on its major ion chemistry and its suitability for drinking, domestic use and irrigation. Water samples from the river were collected and analysed for pH, temperature, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS), turbidity, Cl, SO4 , Ca, Mg, Na and K. Besides major elements, Cu, Zn, Ni, Co, Fe, Mn, Cr, Bi, Cd, Ba, Pb, As, Al, V, Se, Ag, Sr and Li were also determined in this study. The results show that the river water of the area reflects natural factors and is regarded as fresh water and suitable for drinking and domestic use. The calculated values of sodium adsorption ratio (SAR), Mg hazard and salinity hazard indicate that the river water is of high quality and suitable for agricultural and irrigation purposes. This study contributes baseline data for a pristine, forested environment for future reference. 相似文献
298.
Iqbal Mokhtar Mohd Yazid Yahya Mohammed Rafiq Abdul Kadir 《Polymer-Plastics Technology and Engineering》2013,52(10):1007-1015
The objective of this study was to characterize the mechanical behaviour of basalt/HDPE composite under in-vitro condition. Basalt fiber has been performed as an alternative reinforcement material to reduce the domination of the synthetic fibers such as carbon and E-glass fiber in the medical application. Mechanical testing such as tensile, flexural and impact were performed to determine this composite performance before in-vitro testing conducted. Comparisons have been done towards carbon and E-glass using HDPE as a resin. In-vitro testing of basalt/HDPE was conducted in duration 4 weeks. The results shows the basalt/HDPE has a higher mechanical properties compared to E-glass/HDPE and lower compared to carbon/HDPE. Results of tensile and flexural after in-vitro testing are slightly reduced in 5% by week. Charpy impact test of Basalt/HDPE was performed and also experience a reduction in 7% of strength value. Scanning Electron Microscope (SEM) is used to analyze the surface and texture morphology before and after in-vitro testing. No bio-activity or significant changes have been identified at the Basalt/HDPE composite based on the SEM data. It can be concluded that the basalt/HDPE was combined well as a composite material under in-vitro condition as well can be introduce in medical application. 相似文献
299.
Wan Nur Aini Wan Mokhtar Wan Azelee Wan Abu Bakar Wan Nazwanie Wan Abdullah Susilawati Toeman Salmiah Jamal Mat Rosid 《Petroleum Science and Technology》2013,31(21):1741-1747
AbstractIn this work, a series of supported manganese catalyst has been synthesized and utilized in oxidative desulfurization to remove 4,6-dimethyldibenzothiophene (4,6-DMDBT), dibenzothiophene (DBT) and thiophene. The influences of catalyst parameters were investigated including manganese precursors, manganese loading and calcination temperature in details. The synthesized catalyst was characterized by scanning electron microscopy (SEM), N2 adsorption/desorption and X-ray diffraction (XRD) techniques. 90.2% of 4,6-DMDBT, 98.5% of DBT and 95.5% of thiophene conversion were achieved under mild operational conditions using 3Mn(NO3)2/Al2O3 at 500?°C calcination temperature. A slight decrease in desulfurization activity was observed after Mn/Al2O3 catalyst being used in five cycles ODS. 相似文献
300.
Doaa Mokhtar Yehia Yasunobu Yokomizu Daisuke Iioka Toshiro Matsumura 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(1):23-30
In this paper, we show that in a low‐voltage DC distribution system the deliverable power to a load has an upper limit Plim due to the voltage instability at the receiving ends. On the basis of the previously derived concept of Plim, we obtain the dependence of Plim on the distribution line resistance R. In addition, we investigate the influence of the number of loads on Plim. The result shows that a distribution line of lower R causes Plim to be lower. This reduction in Plim becomes more distinct for a larger number of loads. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献